Most personal computers used today support the connection of a second display device. A listing of such devices may include an additional computer monitor, a large screen display device or projector used to display information to an audience, or even a television display that has a compatible connection. There is little doubt that the effectiveness of instructional materials such as classroom, business and other presentations are improved with illustrations. For best effect and retention of audience interest, illustrations should be consecutive, showing incremental changes in the material displayed and perhaps most importantly, show the image with sufficient clarity for the viewer to be able to discern the information contained in the presentation.
When a presenter wishes to generate these illustrations from a presentation or other source of material which was developed for display on a second display device, as previously described, but does not have access to a second device, he or she may still desire to make changes to the source material. Making such changes and then generating illustrations can be time consuming and difficult, detracting from the ultimate goal, that being to communicate a concept to an audience. The presenter may have to adapt an existing source material to be viewed to the primary display of a computer. This may result in the inability to see controls or notes that would normally be displayed on the primary display of a computer. A presenter may also find it difficult to create a presentation for later use in an environment which has display devices unlike those available to the presenter at his or her normal workplace. Examples of such devices may be display projectors and television monitors that have a variety of different display aspect ratios. In order to create a presentation that is displayed correctly on such a display device, a presenter may have to create or make adjustments to a presentation after connecting a computer to the same or similar devices. This process is inefficient and does not allow a presenter to confidently create a presentation in advance. A solution to this inefficiency is the creation of simulated monitor which the presenter or user of the computer may configure to be of the same type or configuration of the type of display device upon which a presentation will be displayed.
Even after the presenter makes such changes to his material, he still must go through a process of selecting and capturing screen images. Past methods of capturing screen images have included using print screen functionality often contained in computer operating systems. Such an approach requires the presenter to identify an image displayed on a computer screen while using a series of keystrokes to “copy” an image and “paste” it into a document. There are also programs that allow a user to capture screen images from within a software user interface that may be configured to store the selected images without the copy and paste steps described above. Examples of such solutions are computer programs such as Snagit® (www.techsmith.com) and Captivate® (www.adobe.com/captivate). Despite the elimination of the “cut” and “paste” steps, users of these existing software programs are still required to manually select and initiate the storage of images created using a program such as PowerPoint® or other, similar computer programs. A major shortcoming of this approach is that it requires the user to create the images ahead of time and in a manner that each image shows an incremental step of the information to be conveyed. Further, using these methods require the user to wait for an image to appear, and then pause to select and copy the image for storage. This process may be that much more difficult and frustrating if the person trying to capture images had to start a presentation, wait for an image to appear, capture that image, and then stop the presentation so that he could paste the image into another document.
An experienced presenter will realize that it is important that illustrative images are captured frequently enough that they do not confuse a viewer. In order for a series of images to best portray the concepts presented during a presentation, those images should convey incremental images that represent a series of steps from one concept to the next. Failure to create incremental images results in a series of summary images which, while they may make good key points, do not provide the viewer with the incremental pieces of information needed to bridge the gap from one concept image to the next.
A solution to the problem of the need for high levels of user involvement required with the image capture approaches just described has been the use of a video camera to record an entire presentation. This approach allows for capture of images as they are displayed on a computer monitor or an overhead projector. While this solves the problem of capturing enough images to avoid the problem of large gaps from one summary image to the next, it suffers from the problem of capturing much more information than is needed, capturing hundreds or even thousands of nearly identical images. As a result of the large number of images, the video files obtained from the use of a video camera are extremely large and difficult to easily store and deliver to potential audiences. In the case of the presenter only having a single monitor is that the image to be recorded is only able to be displayed on what is often a relatively small display which may create difficulties for a video camera's ability to focus at such a short distance. The highly compressed video images (frames) of video files are also of much lower quality than bitmap images captured directly from a computer system.
Other methods of capturing displayed images employ external video capture devices (video grabbing cards) in conjunction with driver software to capture images from a video source. An example of this type of technology is the Encore ENMVG-2 Audio Video Grabber device. These types of external devices require the operator to capture the entire video recording or to select small segments of a video recording and as a result, still suffer from the large file size and image quality problems present with the use of the video camera method previously described.
The present invention provides an improvement to the process whereby the user of the invention may capture images from a computerized device for later use when the user wishes to capture such images from a second monitor but does not have a second monitor available for connection or such a connection would be inconvenient or impossible. The invention allows the user of the invention to capture said images automatically and without continuous actions by the user. The invention allows the user of the invention to optimize the capture of said images so as to capture a sufficient number of images to allow a later viewer of the images to understand the material presented without capturing such a large number of images that the resultant image data file becomes difficult to store and transmit to a later viewer.
In a computer system embodying the principles of the invention, the problems caused by a user of the computer system who wishes to display images to a secondary display device when no such device is available or convenient to connect to the computer system are addressed by providing a method whereby the computer is set up as if it had two displays, and is tricked to display (blindly) content on that (non-existent) secondary display, which is then captured. The capture software allows displaying a preview of the content of the non-existing secondary display on a window on the primary display. The benefit of this method is the ability to capture full screen presentations and still be able to see all controls of the capture process, while having only one monitor/display is connected to the computer system. This method assumes that the computer has the ability to drive a secondary monitor even though it is not connected (and may not exist). Because computer display devices may be any one of several types and configurations, the capture software allows the format of the simulated display to be configured to match that of an actual display device that may later be used to display a presentation. An advantage of this configurability is that a presentation may be created and captured for use on a display device to which the creator of the presentation may not have access prior to a presentation.
In computer software embodying the principles of the invention, the problems associated with the user having to remain actively involved in the image capture process, significant gaps in information content from one image to the next, and the problems associated with managing and distributing large files are addressed by providing a method for automatically capturing full resolution static images from a computing device without the need for any additional hardware, detecting changes to the image and automatically storing single static images when the image has changed an appreciable amount. This approach avoids capturing large numbers of identical images as is the case with a video camera but allows for captures that are frequent enough so that the images captured represent a sufficiently detailed summary of the presented material as to allow the viewer to comprehend the material.
In the present implementation of the invention, the amount of generated data is optimized by a suitable algorithm. In an exemplary embodiment of the algorithm a new full resolution static image (a picture slide) is created when the following are true:
The original picture has changed appreciably (what is reasonable may be pre-set by the user); and/or,
Enough time has passed since the previous picture slide was captured (what is “enough” time may be pre-set); and/or,
The picture is relatively stable (the source data has not changed very much over a predetermined period of time).
The advantages of this algorithm is that it allows the user to initiate a static image capture process using pre-set parameters and then focus on the presentation being created without having to be concerned with the mechanics of the image capture process. If the presenter or operator of the software embodying the algorithm wishes to increase or decrease the amount of detail captured, he or she may choose to adjust the parameters used by the software to determine when an image is captured and stored simply by making adjustments to these parameters from a user interface presented on the user interface of a computer or other device running the image capture software.
Further improvements may be made to implementations of the capture algorithm to improve the ease of use by implementing features such as controls that allow the operator to adjust the image capture parameters using user interface controls such as a sliding control adjustment that may simply be adjusted from more detail to less detail settings without the user having to adjust each parameter separately. Additional functions such as a view of the images being captured and indicators which display the number of images captured and total file size of the captured images may be added to further improve the operator's ability to optimize the image capture process. If the user desires to create a complete presentation, the image capture algorithm may be further combined with an interface to audio or video capture hardware to create a file that combines both an audio or audio/video recording and the images captured by the algorithm whereby the images are keyed to allow for a playback of those images displayed in synchronization to the audio or audio/video recording.
In addition to the novel features and advantages mentioned above, other benefits will be readily apparent from the following descriptions of the drawings and exemplary embodiments.